1. Field of the Invention
The present invention relates generally to toolholders for holding cutting tools used with multi-spindle machines, and more particularly, but not by way of limitation, to an adjustable toolholder designed for use with form tools.
2. Description of the Prior Art
A multi-spindle machine includes a plurality of rotating spindles. A workpiece is mounted in each spindle. The workpiece is rotated by the spindle, and is engaged by a variety of cutting tools to shape the rotating workpiece into a final part.
The various cutting tools are mounted in very rugged holding devices which are bolted to a supporting surface of a cross slide of the machine.
As each spindle of the multi-spindle machine is indexed to the various operating positions of the machine, the cross slide associated with that respective position is advanced toward the rotating workpiece to engage a cutting tool with the rotating workpiece.
As will be appreciated by those skilled in the art, the adjustment of the position of the cutting tool relative to the rotating workpiece is critical to achieving the desired finished cut on the workpiece. Because the cross slide advances to a predetermined position relative to the spindle, this adjustment must be made by first adjusting the position of the cutting tool relative the cross slide upon which it is mounted.
Traditionally, this adjustment has been accomplishment by adjustment of the position of the toolholder upon the cross slide. This is accomplished by using hammers to bump the toolholder to a desired position, and using shims under the toolholder. Through a process of trial and error, the toolholder is bumped toward an appropriate position and/or shimmed to a desired height and finally clamped in position on the cross slide. It will be appreciated that this is a tedious, inefficient and imprecise technique.
Thus, there is a need in the art for a more easily and precisely adjustable positioning of a cutting tool relative to the cross slide upon which it is mounted.
For example, U.S. Pat. No. 3,566,723 to Oborne discloses a cutting toolholder for positioning a cutting tool against a workpiece. The holder includes facilities for adjustment of the tool so that it may be raised or lowered, and moved laterally, longitudinally and angularly with respect to the workpiece.
Although the Oborne device achieves to some degree some of the results to which the present invention is directed, it will be appreciated that in many aspects the present invention is vastly improved relative to the Oborne structure. This is particularly true with regard to the means for angular adjustment provided by the present invention, and with regards to the carrier block construction, clamping and adjustment means of the present invention for adjusting the height of the cutting tool.
U.S. Pat. No. 4,631,994 to Jester, et al., discloses another construction for an adjustable holder for a cutting tool which allows both linear and angular adjustment.
U.S. Pat. No. 4,750,392 to Hong, provides a hollow housing having an extendible body to provide fore and aft movement, and having a rotatable tool holding head mounted upon the body to provide angular movement.
Other prior art references located in a preliminary patent ability search directed to the present invention include the following:
U.S. Pat. No. 4,879,930 to Von Haas PA1 U.S. Pat. No. 4,422,356 to Pertle PA1 U.S. Pat. No. 4,389,144 to Sipos PA1 U.S. Pat. No. 4,080,854 to Peterson PA1 U.S. Pat. No. 3,546,759 to Sirola PA1 U.S. Pat. No. 2,903,781 to Hudson
Thus, it is seen that there is a need in the art for an improved adjustable toolholder apparatus which allows the position of a cutting tool to be adjusted linearly, angularly, and in height.